Field
The invention relates generally to nuclear power plants and, more particularly, to the inspection and of evaluation of components within the containment of a nuclear power plant.
Description of the Related Art
Nuclear power plants are generally well known. Nuclear power plants can generally be stated as comprising a reactor that includes one or more fuel cells and a coolant system that drives a steam turbine which operates an electrical generator. The various components of the nuclear power plant are subject to wear from mechanical vibration, corrosion, and other mechanisms. It thus is necessary to periodically inspect the components for wear in order to preferably avoid failure of the components. While numerous methodologies have been employed for performing such inspection, such methodologies have not been without limitation.
Since reactors typically are situated within a containment, such reactors can often have areas of limited access that nevertheless need to be inspected on a periodic basis. A known methodology that has been employed for inspecting components situated at limited access locations within a nuclear containment has been to deliver to a limited access location an elongated tool having one or more flexible regions, with the tool carrying a testing element that is used to perform the inspection process. The elongated tool typically includes a plurality of elongated portions each separated from one another by a flexible portion, with at least one of the portions having expandable legs that can be deployed and caused to engage an interior surface of a fluid flow channel. The component carrying the testing element can then be rotated (with respect to the portion having the expandable legs) to perform the inspection operation. While such methodologies have been generally effective for their intended purposes, they have not been without limitation.
Since such tools typically have one element that is rotatable with respect to another element, the electrical connection between the testing element and the non-rotating components have needed to include a number of moveable connection devices such as slip rings and the like, which have resulted in intermittent losses of testing data. Moreover, since a component of such a tool is typically both rotatable and pivotable with respect to other portions of the tool, the data cable that extends from the testing element across the regions of such rotation and pivoting can become stretched and its conductors occasionally broken, which results in loss of signal.
Known methodologies of inserting the tool into the limited access locations have included manual insertion and the use of a submersible device to carry the tool to the limited access location. Manual insertion requires extensive effort and patience and must be performed by highly skilled individuals. The use of submersible devices has increased the speed of inspection somewhat, but the carrying of the tool to a limited access location with a submersible device has still required significant time and effort to properly position the submersible device in order to clamp it to the reactor in the vicinity of the limited access location and to enable it to insert the tool into the limited access location. It thus would be desirable to provide a system that overcomes such known shortcomings in the relevant art.